System for managing transitions between media content items

ABSTRACT

A system for playing media content items operates to provide smooth transitions between the media content items to continuously support a user&#39;s repetitive motion activity. The system can generate crossfade data containing information for transitions between media content items. The mix-in and mix-out points for the transitions are calculated to eliminate one or more portions of media content items that have lower musical energy than a majority portion of the items, and to maintain substantially consistent and/or stable musical energy (e.g., audio power or sound power) throughout the media content items including transitions therebetween.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a Continuation of U.S. application Ser. No.16/136,789 filed Sep. 20, 2018, which is a Continuation of U.S.application Ser. No. 14/944,972, filed Nov. 18, 2015, which claimspriority to U.S. Application No. 62/163,865 filed on May 19, 2015 andentitled SYSTEM FOR MANAGING TRANSITIONS BETWEEN MEDIA CONTENT ITEMS,the disclosures of which are hereby incorporated by reference in theirentireties.

BACKGROUND

Running, as well as many other recreation or fitness activities,includes repetitive motions. For example, running and walking involverepetitive steps, biking involves repetitive rotational movements,rowing involves repetitive strokes, and swimming involves repetitivestrokes and kicks. There are of course many other recreation and fitnessactivities that also include various repetitive motions. Theserepetitive motion activities may be performed in place (e.g., using atreadmill, stationary bike, rowing machine, swimming machine, etc.) orin motion (e.g., on roads, trails, or tracks or in a pool or body ofwater, etc.). Cadence refers to the frequency of these repetitivemotions and is often measured in terms of motions per minute (e.g.,steps per minute, rotations per minute, strokes per minute, or kicks perminute).

Many people enjoy consuming media content, such as listening to audiocontent or watching video content, while running or engaging in otherrepetitive-motion activities. Examples of audio content include songs,albums, podcasts, audiobooks, etc. Examples of video content includemovies, music videos, television episodes, etc. Using a mobile phone orother media-playback device a person can access large catalogs of mediacontent. For example, a user can access an almost limitless catalog ofmedia content through various free and subscription-based streamingservices. Additionally, a user can store a large catalog of mediacontent on his or her mobile device.

This nearly limitless access to media content introduces new challengesfor users. For example, it may be difficult to find or select the rightmedia content that complements a particular moment during a run or otherrepetitive-motion activity. Further, media content often containportions that do not complement the repetitive motion activity as wellas other portions.

SUMMARY

In general terms, this disclosure is directed to a system for managingtransitions between media content items. In one possible configurationand by non-limiting example, the system operates to generate crossfadedata containing information for transitions between media content itemsto continuously support a user's repetitive motion activity, and playback the media content items based on the crossfade data. Variousaspects are described in this disclosure, which include, but are notlimited to, the following aspects.

One aspect is a method of playing back media content items tocontinuously support a repetitive motion activity. The method mayinclude acquiring, using at least one computing device, a user'scadence; obtaining, using the at least one computing device, crossfadedata of first and second media content items, the crossfade dataincluding a mix-out point of the first media content item and a mix-inpoint of the second media content item; playing back the first mediacontent item on the at least one computing device, the first mediacontent item having a tempo corresponding to the user's cadence; andplaying back the second media content item on the at least one computingdevice with the mix-in point of the second media content item matchingthe mix-out point of the first media content item, the second mediacontent item having a tempo corresponding to the user's cadence.

Another aspect is a method of generating data for transitions betweenmedia content items to continuously support a repetitive motionactivity. The method may include determining mix-in points of mediacontent items; determining mix-out points of the media content items,the mix-out point of a media content item configured to match the mix-inpoint of a subsequent media content item as the first and second mediacontent items are played back; and generating data with the mix-in andmix-out points for the media content items. The mix-in point for a mediacontent item is determined such that a musical energy of the mediacontent item between a beginning of the media content item and themix-in point of the media content item is substantially lower than amusical energy of the media content item between the mix-in point of themedia content item and the mix-out point of the media content item. Themix-out point of the media content item is determined such that amusical energy of the media content item between the mix-out point ofthe media content item and an end of the media content item issubstantially lower than the musical energy of the media content itembetween the mix-in point of the media content item and the mix-out pointof the media content item.

Yet another aspect is acomputer-readable storage medium comprisingsoftware instructions that, when executed, cause at least one computingdevice to: acquire a user's cadence; obtain crossfade data of first andsecond media content items, the crossfade data including a mix-out pointof the first media content item and a mix-in point of the second mediacontent item; play back the first media content item on the at least onecomputing device, the first media content item having a tempocorresponding to the user's cadence; and play back the second mediacontent item on the at least one computing device with the mix-in pointof the second media content item matching the mix-out point of the firstmedia content item, the second media content item having a tempocorresponding to the user's cadence.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example system for managing transitions betweenmedia content items to continuously support a repetitive motionactivity.

FIG. 2 is a schematic illustration of an example system for managingtransitions between media content items to continuously support arepetitive motion activity.

FIG. 3 is a flowchart illustrating an example method for operating thesystem for managing transitions between media content items tocontinuously support a repetitive motion activity.

FIG. 4 illustrates an example musical energy used to determine mix-inand mix-out points of media content items.

FIG. 5 illustrates an example method of performing an operation of FIG.3.

FIG. 6 is a flowchart illustrating an example method of determining amix-in point for a media content item.

FIG. 7 is a flowchart illustrating an example method of determining amix-out point for the media content item.

FIG. 8 schematically illustrates variations in musical energy over anentire time of the media content item.

FIG. 9 illustrates an example crossfade data including information aboutthe mix-in points and mix-out points of the media content items.

FIG. 10 is a flowchart illustrating an example method of performing anoperation of FIG. 3.

FIG. 11 illustrates the method of FIG. 10 with two media content items.

FIG. 12 illustrates an example method of aligning the mix-out point of afirst media content item and the mix-in point of a second media contentitem.

FIG. 13 is a flowchart illustrating an example method of performing anoperation of FIG. 3.

FIG. 14 illustrates the method of FIG. 13 with two media content items.

FIG. 15 is an example user interface for selecting crossfade duration.

DETAILED DESCRIPTION

Various embodiments will be described in detail with reference to thedrawings, wherein like reference numerals represent like parts andassemblies throughout the several views. Reference to variousembodiments does not limit the scope of the claims attached hereto.Additionally, any examples set forth in this specification are notintended to be limiting and merely set forth some of the many possibleembodiments for the appended claims.

Users of media-playback devices often consume media content whileengaging in various activities, including repetitive motion activities.As noted above, examples of repetitive-motion activities may includeswimming, biking, running, rowing, and other activities. Consuming mediacontent may include one or more of listening to audio content, watchingvideo content, or consuming other types of media content. For ease ofexplanation, the embodiments described in this application are presentedusing specific examples. For example, audio content (and in particularmusic) is described as an example of one form of media consumption. Asanother example, running is described as one example of arepetitive-motion activity. However, it should be understood that thesame concepts are equally applicable to other forms of media consumptionand to other forms of repetitive-motion activities, and at least someembodiments include other forms of media consumption and/or other formsof repetitive-motion activities.

The users may desire that the media content fits well with theparticular repetitive activity. For example, a user who is running maydesire to listen to music with a beat that corresponds to the user'scadence. Beneficially, by matching the beat of the music to the cadence,the user's performance or enjoyment of the repetitive-motion activitymay be enhanced. This desire cannot be met with traditionalmedia-playback devices and media-delivery systems.

In general, the present disclosure is directed to a system for playingmedia content items with smooth transitions to continuously support auser's repetitive motion activity. The system can generate crossfadedata containing information for transitions between media content items.The crossfade data can include mix-in and mix-out points of mediacontent items that are used to at least partially overlap media contentitems. The mix-in and mix-out points are calculated to eliminate one ormore portions of media content items that have lower musical energy thana majority portion of the items, and to maintain substantiallyconsistent and/or stable musical energy (e.g., audio power or soundpower) throughout the media content items including transitionstherebetween. For example, the mix-in and mix-out points are determinedto crossfade media content items while maintaining an equal powerthroughout the media content items. A media-playback device is providedto acquire a user's cadence and play back a plurality of media contentitems having a tempo corresponding to the cadence while the userperforms a repetitive motion activity. The media-playback deviceoperates to play the media content items such that a mix-out point of amedia content item matches a mix-in point of a subsequent media contentitem, thereby generally consistently maintain a musical energy (e.g.,audio power or sound power) during transition between the two mediacontent items. In certain examples, the media-playback device operatesto match at least one beat around the mix-out point of the media contentitem with at least one beat around the mix-out point of the subsequentmedia content item to provide a consistent tempo over the transitionbetween the media content items.

As such, the system of the present disclosure can play a plurality ofmedia content items to continuously support a user's repetitive motionactivity without distracting a user's cadence. The system is configuredto ensure that a musical energy suitable for the repetitive motionactivity continues over transitions of different media content items.The system provides a simple, efficient solution to transitions betweenmedia content items with consistent tempo and musical energy (e.g.,audio power or sound power). In certain examples, the management processfor transitions between media content items is executed in a servercomputing device, rather than the media-playback device. Accordingly,the media-playback device can save its resources for playing back mediacontent items with such transitions, and the management process can beefficiently maintained and conveniently modified as appropriate withoutinteracting with the media-playback device.

FIG. 1 illustrates an example system 100 for managing transitionsbetween media content items to continuously support a repetitive motionactivity. The example system 100 includes a media-playback device 102and a media-delivery system 104. In some embodiments, a cadence-basedmedia content crossfade engine 112 runs on the media-playback device102, and a media mix data generation engine 240 runs on themedia-delivery system 104. The system 100 communicates across a network106. Also shown are a user U who is running. The user U's upcoming stepsS are shown as well. A step represents a single strike of the runner'sfoot upon the ground.

The media-playback device 102 operates to play media content items toproduce media output 110. In some embodiments, the media content itemsare provided by the media-delivery system 104 and transmitted to themedia-playback device 102 using the network 106. A media content item isan item of media content, including audio, video, or other types ofmedia content, which may be stored in any format suitable for storingmedia content. Non-limiting examples of media content items includesongs, albums, music videos, movies, television episodes, podcasts,other types of audio or video content, and portions or combinationsthereof.

The media-playback device 102 plays media content for the user based onthe user's cadence. In the example shown, the media output 110 includesmusic with a tempo that corresponds to the user's cadence. The tempo (orrhythm) of music refers to the frequency of the beat and is typicallymeasured in beats per minute (BPM). The beat is the basic unit of rhythmin a musical composition (as determined by the time signature of themusic). Accordingly, in the example shown, the user U's steps occur atthe same frequency as the beat of the music.

For example, if the user U is running at a cadence of 180 steps perminute, the media-playback device 102 may play a media content itemhaving a tempo equal to or approximately equal to 180 BPM. In otherembodiments, the media-playback device 102 plays a media content itemhaving a tempo equal or approximately equal to the result of dividingthe cadence by an integer such as a tempo that is equal to orapproximately equal to one-half (e.g., 90 BPM when the user is runningat a cadence of 180 steps per minute), one-fourth, or one-eighth of thecadence. Alternatively, the media-playback device 102 plays a mediacontent item having a tempo that is equal or approximately equal to aninteger multiple (e.g., 2×, 4×, etc.) of the cadence. Further, in someembodiments, the media-playback device 102 operates to play multiplemedia content items including one or more media content items having atempo equal to or approximately equal to the cadence and one or moremedia content items have a tempo equal or approximately equal to theresult of multiplying or dividing the cadence by an integer. Variousother combinations are possible as well.

In some embodiments, the media-playback device 102 operates to playmusic having a tempo that is within a predetermined range of a targettempo. In at least some embodiments, the predetermined range is plus orminus 2.5 BPM. For example, if the user U is running at a cadence of 180steps per minute, the media-playback device 102 operates to play musichaving a tempo of 177.5-182.5 BPM. Alternatively, in other embodiments,the predetermined range is itself in a range from 1 BPM to 10 BPM. Otherranges of a target tempo are also possible.

Further, in some embodiments, the media content items that are playedback on the media-playback device 102 have a tempo equal to orapproximately equal to a user U's cadence after it is rounded. Forexample, the cadence may be rounded to the nearest multiple of 2.5, 5,or 10 and then the media playback device 102 plays music having a tempoequal to or approximately equal to the rounded cadence. In yet otherembodiments, the media-playback device 102 uses the cadence to select apredetermined tempo range of music for playback. For example, if theuser U's cadence is 181 steps per minute, the media-playback device 102may operate to play music from a predetermined tempo range of 180-184.9BPM; while if the user U's cadence is 178 steps per minute, themedia-playback device 102 may operate to play music from a predeterminedtempo range of 175-179.9 BPM.

The cadence-based media content crossfade engine 112 operates to makesmooth transitions between different media content items which areplayed on the media-playback device 102 during a user's repetitivemotion activity. The crossfade engine 112 is configured to overlap atleast portion of media content items based on mix-in and mix-out pointsgenerated by the media mix data generation engine 240, therebymaintaining a constant output level to continuously support the user'srepetitive motion activity without interruption. An example of thecadence-based media content crossfade engine 112 is described andillustrated in more detail with reference to FIGS. 10-15.

The media mix data generation engine 240 operates to generate media mixdata to be used for crossfading cadence-based media content items. Asdescribed herein, such media mix data can be incorporated inrepetitive-motion activity media metadata 232 (FIG. 2). An example ofthe media mix data generation engine 240 is described and illustrated inmore detail with reference to FIGS. 5-9.

FIG. 2 is a schematic illustration of an example system 100 for managingtransitions between media content items to continuously support arepetitive motion activity. In FIG. 2, the media-playback device 102,the media-delivery system 104, and the network 106 are shown. Also shownare the user U and a satellite S.

As noted above, the media-playback device 102 operates to play mediacontent items. In some embodiments, the media-playback device 102operates to play media content items that are provided (e.g., streamed,transmitted, etc.) by a system external to the media-playback devicesuch as the media-delivery system 104, another system, or a peer device.Alternatively, in some embodiments, the media-playback device 102operates to play media content items stored locally on themedia-playback device 102. Further, in at least some embodiments, themedia-playback device 102 operates to play media content items that arestored locally as well as media content items provided by other systems.

In some embodiments, the media-playback device 102 is a computingdevice, handheld entertainment device, smartphone, tablet, watch,wearable device, or any other type of device capable of playing mediacontent. In yet other embodiments, the media-playback device 102 is alaptop computer, desktop computer, television, gaming console, set-topbox, network appliance, blue-ray or DVD player, media player, stereo, orradio.

In at least some embodiments, the media-playback device 102 includes alocation-determining device 150, a touch screen 152, a processing device154, a memory device 156, a content output device 158, acadence-acquiring device 160, and a network access device 162. Otherembodiments may include additional, different, or fewer components. Forexample, some embodiments may include a recording device such as amicrophone or camera that operates to record audio or video content. Asanother example, some embodiments do not include one or more of thelocation-determining device 150 and the touch screen 152.

The location-determining device 150 is a device that determines thelocation of the media-playback device 102. In some embodiments, thelocation-determining device 150 uses one or more of the followingtechnologies: Global Positioning System (GPS) technology which mayreceive GPS signals 170 from satellites S, cellular triangulationtechnology, network-based location identification technology, Wi-Fipositioning systems technology, and combinations thereof.

The touch screen 152 operates to receive an input 172 from a selector(e.g., a finger, stylus etc.) controlled by the user U. In someembodiments, the touch screen 152 operates as both a display device anda user input device. In some embodiments, the touch screen 152 detectsinputs based on one or both of touches and near-touches. In someembodiments, the touch screen 152 displays a user interface 164 forinteracting with the media-playback device 102. As noted above, someembodiments do not include a touch screen 152. Some embodiments includea display device and one or more separate user interface devices.Further, some embodiments do not include a display device.

In some embodiments, the processing device 154 comprises one or morecentral processing units (CPU). In other embodiments, the processingdevice 154 additionally or alternatively includes one or more digitalsignal processors, field-programmable gate arrays, or other electroniccircuits.

The memory device 156 operates to store data and instructions. In someembodiments, the memory device 156 stores instructions for amedia-playback engine 166 that includes a cadence-based media contentselection engine 168 and the cadence-based media content crossfadeengine 112.

The memory device 156 typically includes at least some form ofcomputer-readable media. Computer readable media include any availablemedia that can be accessed by the media-playback device 102. By way ofexample, computer-readable media include computer readable storage mediaand computer readable communication media.

Computer readable storage media includes volatile and nonvolatile,removable and non-removable media implemented in any device configuredto store information such as computer readable instructions, datastructures, program modules, or other data. Computer readable storagemedia includes, but is not limited to, random access memory, read onlymemory, electrically erasable programmable read only memory, flashmemory and other memory technology, compact disc read only memory, blueray discs, digital versatile discs or other optical storage, magneticcassettes, magnetic tape, magnetic disk storage or other magneticstorage devices, or any other medium that can be used to store thedesired information and that can be accessed by the media-playbackdevice 102. In some embodiments, computer readable storage media isnon-transitory computer readable storage media.

Computer readable communication media typically embodies computerreadable instructions, data structures, program modules or other data ina modulated data signal such as a carrier wave or other transportmechanism and includes any information delivery media. The term“modulated data signal” refers to a signal that has one or more of itscharacteristics set or changed in such a manner as to encode informationin the signal. By way of example, computer readable communication mediaincludes wired media such as a wired network or direct-wired connection,and wireless media such as acoustic, radio frequency, infrared, andother wireless media. Combinations of any of the above are also includedwithin the scope of computer readable media.

The content output device 158 operates to output media content. In someembodiments, the content output device 158 generates media output 110for the user U. Examples of the content output device 158 include aspeaker, an audio output jack, a Bluetooth transmitter, a display panel,and a video output jack. Other embodiments are possible as well. Forexample, the content output device 158 may transmit a signal through theaudio output jack or Bluetooth transmitter that can be used to reproducean audio signal by a connected or paired device such as headphones or aspeaker.

The cadence-acquiring device 160 operates to acquire a cadenceassociated with the user U. In at least some embodiments, thecadence-acquiring device 160 operates to determine cadence directly andincludes one or more accelerometers or other motion-detectingtechnologies. Alternatively, the cadence-acquiring device 160 operatesto receive data representing a cadence associated with the user U. Forexample, in some embodiments, the cadence-acquiring device 160 operatesto receive data from a watch, bracelet, foot pod, chest strap, shoeinsert, anklet, smart sock, bicycle computer, exercise equipment (e.g.,treadmill, rowing machine, stationary cycle), or other device fordetermining or measuring cadence. Further, in some embodiments, thecadence-acquiring device 160 operates to receive a cadence value inputby the user U or another person.

The network access device 162 operates to communicate with othercomputing devices over one or more networks, such as the network 106.Examples of the network access device include wired network interfacesand wireless network interfaces. Wireless network interfaces includesinfrared, BLUETOOTH® wireless technology, 802.11a/b/g/n/ac, and cellularor other radio frequency interfaces in at least some possibleembodiments.

The media-playback engine 166 operates to play back one or more of themedia content items (e.g., music) to encourage the running of the userU. As described herein, the media-playback engine 166 is configured tocommunicate with the media-delivery system 104 to receive one or moremedia content items (e.g., through the stream media 218) based on thecadence detected by the cadence-acquiring device 160.

The cadence-based media content selection engine 168 operates toretrieve one or more media content items based on a cadence of the userU acquired by the media-playback device 102 (e.g., the cadence-acquiringdevice 160 thereof). In some embodiments, the cadence-based mediacontent selection engine 168 is configured to send a request to themedia-delivery system 104 for media content items having a tempocorresponding to the acquired cadence, and receive information (e.g.,the repetitive-motion activity media metadata 232) about such mediacontent items for playback during the user's performance of repetitivemotion activity.

In some embodiments, the cadence-based media content crossfade engine112 is included in the media-playback engine 166. The cadence-basedmedia content crossfade engine 112 operates to make smooth changeoverbetween different media content items during a user's repetitive motionactivity, thereby continuously supporting the repetitive motionactivity. An example of the cadence-based media content crossfade engine112 is described and illustrated in more detail with reference to FIGS.10-15.

The network 106 is an electronic communication network that facilitatescommunication between the media-playback device 102 and themedia-delivery system 104. An electronic communication network includesa set of computing devices and links between the computing devices. Thecomputing devices in the network use the links to enable communicationamong the computing devices in the network. The network 106 can includerouters, switches, mobile access points, bridges, hubs, intrusiondetection devices, storage devices, standalone server devices, bladeserver devices, sensors, desktop computers, firewall devices, laptopcomputers, handheld computers, mobile telephones, and other types ofcomputing devices.

In various embodiments, the network 106 includes various types of links.For example, the network 106 can include wired and/or wireless links,including Bluetooth, ultra-wideband (UWB), 802.11, ZigBee, cellular, andother types of wireless links. Furthermore, in various embodiments, thenetwork 106 is implemented at various scales. For example, the network106 can be implemented as one or more local area networks (LANs),metropolitan area networks, subnets, wide area networks (such as theInternet), or can be implemented at another scale. Further, in someembodiments, the network 106 includes multiple networks, which may be ofthe same type or of multiple different types.

The media-delivery system 104 comprises one or more computing devicesand operates to provide media content items to the media-playbackdevices 102 and, in some embodiments, other media-playback devices aswell. The media-delivery system 104 includes a media server 180 and arepetitive-motion activity server 182. In at least some embodiments, themedia server 180 and the repetitive-motion activity server 182 areprovided by separate computing devices. In other embodiments, the mediaserver 180 and the repetitive-motion activity server 182 are provided bythe same computing devices. Further, in some embodiments, one or both ofthe media server 180 and the repetitive-motion activity server 182 areprovided by multiple computing devices. For example, the media server180 and the repetitive-motion activity server 182 may be provided bymultiple redundant servers located in multiple geographic locations.

The media server 180 operates to transmit stream media 218 tomedia-playback devices such as the media-playback device 102. In someembodiments, the media server 180 includes a media server application184, a processing device 186, a memory device 188, and a network accessdevice 190. The processing device 186, memory device 188, and networkaccess device 190 may be similar to the processing device 154, memorydevice 156, and network access device 162 respectively, which have eachbeen previously described.

In some embodiments, the media server application 184 operates to streammusic or other audio, video, or other forms of media content. The mediaserver application 184 includes a media stream service 194, a media datastore 196, and a media application interface 198. The media streamservice 194 operates to buffer media content such as media content items206, 208, and 210, for streaming to one or more streams 200, 202, and204.

The media application interface 198 can receive requests or othercommunication from media-playback devices or other systems, to retrievemedia content items from the media server 180. For example, in FIG. 2,the media application interface 198 receives communication 234 from themedia-playback engine 166.

In some embodiments, the media data store 196 stores media content items212, media content metadata 214, and playlists 216. The media data store196 may comprise one or more databases and file systems. Otherembodiments are possible as well. As noted above, the media contentitems 212 may be audio, video, or any other type of media content, whichmay be stored in any format for storing media content.

The media content metadata 214 operates to provide various informationassociated with the media content items 212. In some embodiments, themedia content metadata 214 includes one or more of title, artist name,album name, length, genre, mood, era, etc. The playlists 216 operate toidentify one or more of the media content items 212. In someembodiments, the playlists 216 identify a group of the media contentitems 212 in a particular order. In other embodiments, the playlists 216merely identify a group of the media content items 212 withoutspecifying a particular order. Some, but not necessarily all, of themedia content items 212 included in a particular one of the playlists216 are associated with a common characteristic such as a common genre,mood, or era.

The repetitive-motion activity server 182 operates to providerepetitive-motion activity-specific information about media contentitems to media-playback devices. In some embodiments, therepetitive-motion activity server 182 includes a repetitive-motionactivity server application 220, a processing device 222, a memorydevice 224, and a network access device 226. The processing device 222,memory device 224, and network access device 226 may be similar to theprocessing device 154, memory device 156, and network access device 162respectively, which have each been previously described.

In some embodiments, repetitive-motion activity server application 220operates to transmit information about the suitability of one or moremedia content items for playback during a particular repetitive-motionactivity. The repetitive-motion activity server application 220 includesa repetitive-motion activity interface 228 and a repetitive-motionactivity media metadata store 230.

In some embodiments, the repetitive-motion activity server application220 may provide a list of media content items at a particular tempo to amedia-playback device in response to a request that includes aparticular cadence value. Further, in some embodiments, the mediacontent items included in the returned list will be particularlyrelevant for the repetitive motion activity in which the user is engaged(for example, if the user is running, the returned list of media contentitems may include only media content items that have been identified asbeing highly runnable).

The repetitive-motion activity interface 228 operates to receiverequests or other communication from media-playback devices or othersystems to retrieve information about media content items from therepetitive-motion activity server 182. For example, in FIG. 2, therepetitive-motion activity interface 228 receives communication 236 fromthe media-playback engine 166.

In some embodiments, the repetitive-motion activity media metadata store230 stores repetitive-motion activity media metadata 232. Therepetitive-motion activity media metadata store 230 may comprise one ormore databases and file systems. Other embodiments are possible as well.

The repetitive-motion activity media metadata 232 operates to providevarious information associated with media content items, such as themedia content items 212. In some embodiments, the repetitive-motionactivity media metadata 232 provides information that may be useful forselecting media content items for playback during a repetitive-motionactivity. For example, in some embodiments, the repetitive-motionactivity media metadata 232 stores runnability scores for media contentitems that corresponds to the suitability of particular media contentitems for playback during running. As another example, in someembodiments, the repetitive-motion activity media metadata 232 storestimestamps (e.g., start and end points) that identify portions of amedia content items that are particularly well-suited for playbackduring running (or another repetitive-motion activity).

Each of the media-playback device 102 and the media-delivery system 104can include additional physical computer or hardware resources. In atleast some embodiments, the media-playback device 102 communicates withthe media-delivery system 104 via the network 106.

Although in FIG. 2 only a single media-playback device 102 andmedia-delivery system 104 are shown, in accordance with someembodiments, the media-delivery system 104 can support the simultaneoususe of multiple media-playback devices, and the media-playback devicecan simultaneously access media content from multiple media-deliverysystems. Additionally, although FIG. 2 illustrates a streaming mediabased system for managing transitions between media content items basedon a user's cadence, other embodiments are possible as well. Forexample, in some embodiments, the media-playback device 102 includes amedia data store 196 and the media-playback device 102 is configured toperform management of transitions between media content items based on auser's cadence without accessing the media-delivery system 104. Furtherin some embodiments, the media-playback device 102 operates to storepreviously streamed media content items in a local media data store.

In at least some embodiments, the media-delivery system 104 can be usedto stream, progressively download, or otherwise communicate music, otheraudio, video, or other forms of media content items to themedia-playback device 102 based on a cadence acquired by thecadence-acquiring device 160 of the media-playback device 102. Inaccordance with an embodiment, a user U can direct the input 172 to theuser interface 164 to issue requests, for example, to playback mediacontent corresponding to the cadence of a repetitive motion activity onthe media-playback device 102.

FIG. 3 is a flowchart illustrating an example method 300 for operatingthe system 100 for managing transitions between media content items tocontinuously support a repetitive motion activity. In some embodiments,the method 300 includes operations 302 and 304.

At the operation 302, at least some of media content items are analyzedto determine mix-in and mix-out points thereof based on musical energy.In some embodiments, the operation 302 is performed by themedia-delivery system 104 (e.g., the media mix data generation engine240 thereof). In other embodiments, the operation 302 is performed byone or more other computing devices. A musical energy of a media contentitem is defined to represent one or more musical attributes of the mediacontent item, as described in more detail with reference to FIG. 4. Insome embodiments, the mix-in and mix-out points are included in therepetitive-motion activity media metadata 232. In other embodiments, themix-in and mix-out points are stored in different forms. An example ofthe operation 302 is described and illustrated in more detail withreference to FIG. 5.

At the operation 304, the media-playback device 102 operates tocrossfade media content items based on the mix-in and mix-out points ofthe items as the device 102 plays back the items in order during auser's repetitive motion activity. In other embodiments, the operation304 can be performed by one or more other computing devices. An exampleof the operation 304 is described and illustrated in more detail withreference to FIG. 10.

FIG. 4 illustrates an example musical energy 310 that is used todetermine mix-in and mix-out points of media content items. In someembodiments, the musical energy 310 of a media content item iscalculated based on an audio signal 312. In other embodiments, themusical energy 310 is calculated based on one or more musical attributes314. In yet other embodiments, the musical energy 310 is calculatedbased on a combination of the audio signal 312 and one or more musicalattributes 314.

In some embodiments, the musical energy 310 is correlated with a levelof the audio signal 312. The audio signal 312 is a representation ofsound and can be characterized by various parameters, such as bandwidth,power level (measured in bels or decibel), and voltage level.

With the audio signal 312, in some embodiments, the musical energy 310can be representative of audio power. Audio power can be defined as anelectrical power transferred from an audio amplifier to a loudspeaker.The audio power can be measured in watts. A loudspeaker is anelectroacoustic transducer, which converts an electrical audio signalinto a corresponding sound. In some embodiments, such a loudspeaker isimplemented as the content output device 158 (e.g., headphones or aspeaker). In some embodiments, the audio amplifier is limited in theelectrical energy it can amplify, and the loudspeaker is limited in theelectrical energy they can convert to sound energy without distortingthe audio signal or being damaged. The audio power can be calculated invarious known manners.

In other embodiments, the musical energy 310 is representative of soundpower (also referred to as acoustic power), which is a sound energyemitted, reflected, transmitted, or received, per unit item, which canbe measured in watts. Sound power can be a rough measurement of theloudness of a particular sound while there are other factors (e.g., thesound's frequency or the loss of sound intensity due to distance fromthe sound's source) that affect the human perception of sound.

In addition or alternatively to the audio signal 312, the musical energy310 can be correlated with one or more of the musical attributes 314.The music attributes 314 are characteristics, dimensions, or elementstaken as parts or components of music. The music attributes 314 aredefined with various parameters, such as tempo, pitch, dynamics,articulation, timbre, order, and any other elements. In someembodiments, tempo indicates a speed or pace of a given piece and isusually indicated in beats per minute (BPM), as described above. Pitchis a property that allows the ordering of sounds on a frequency-relatedscale. In some embodiments, pitch can be quantified as a frequency.Dynamics can refer to the volume of a sound or note. In otherembodiments, dynamics can also refer to other aspects of the executionof a given piece, either stylistic (e.g., staccato, legato, etc.) orfunctional (velocity, etc.). Articulation refers to the musicalperformance technique that affects the transition or continuity on asingle note, or between multiple notes or sounds. Timbre is the qualityof a musical note, sound, or tone that distinguishes different types ofsound production, such as voices and musical instruments, stringinstruments, wind instruments, and percussion instruments. The physicalcharacteristics of sound that determine the perception of timbre includespectrum and envelope. Order is the specific arrangement of a set ofdiscrete entities, or parameters, such as pitch, dynamics and timbre.

In some embodiments, the musical energy 310 is in a functionalrelationship with the audio signal 312, one or more of the musicalattributes 314, or a combination of the audio signal 312 and one or moreof the musical attributes 314. For example, the musical energy 310 canbe obtained by one or more audio analysis tools of various types.

Although the musical energy 310 is illustrated to be associated with theaudio signal 312 and/or the musical attributes 314, other embodiments ofthe musical energy 310 can represent one or more other aspects of acontent media item, which are suitable to support user's repetitivemotion activities.

FIG. 5 illustrates an example method 330 of performing the operation 302of FIG. 3. In some embodiments, the method 330 includes operations 332,334, and 336.

In some embodiments, the media-delivery system 104 including the mediamix data generation engine 240 is configured to execute the method 330.Although it is described in this document that the media-delivery system104 (including the media mix data generation engine 240) is used toperform the method 330, it is apparent that the method 330 can beperformed by other computing devices in other embodiments.

At the operation 332, the media-delivery system 104 operates to maintainmedia content items 212 in the media data store 196. In otherembodiments, media content items 212 can be stored in other devices,such as independent computing devices or the media-playback device 102.

At the operation 334, the media-delivery system 104 (e.g., the media mixdata generation engine 240) operates to determine mix-in points (T_(IN))and mix-out points (T_(OUT)) (FIG. 8) for at least some of the mediacontent items 212. An example of the operation 334 is illustrated anddescribed in more detail with reference to FIGS. 6-9.

At the operation 336, the media-delivery system 104 operates to generatedata (e.g., crossfade data 400 in FIG. 9) with the mix-in and mix-outpoints determined in the operation 334. In other embodiments, the mix-inand mix-out points are maintained as other data from the media metadata232. For example, the media metadata 232 can be populated with themix-in and mix-out points.

Referring to FIGS. 6-8, a method of determining mix-in and mix-outpoints of a media content item 212 is described. In particular, FIG. 6is a flowchart illustrating an example method 350 of determining amix-in point (T_(IN)) for a media content item 212, and FIG. 7 is aflowchart illustrating an example method of determining a mix-out point(T_(OUT)) for the media content item 212. FIG. 8 schematicallyillustrates variations in musical energy (E) over the entire time (T) ofthe media content item 212.

The methods 350 and 370 can be executed by the media mix data generationengine 240. Although it is described that the media mix data generationengine 240 is used to perform the method 350 herein, it is apparent thatthe method 350 can be performed by other computing devices in otherembodiments.

Referring to FIG. 6, some embodiments of the method 350 includeoperations 352, 354, 356, 358, and 360.

At the operation 352, the media mix data generation engine 240 operatesto determine a predetermined beginning portion of a media content item212 from the beginning (T=0) of the media content item 212. In someembodiments, the predetermined beginning portion is a first portion of aplurality of identically-divided portions of the media content item 212.For example, as illustrated in FIG. 8, where the media content item 212is divided by six portions having the same length, the predeterminedbeginning portion of the media content item 212 is the first portion(P1) of the media content item 212, which is a portion of the mediacontent item 212 in a time range of zero to a sixth (T_(f)/6) of theentire time length (T_(f)). In other embodiments, the predeterminedbeginning portion can be defined in different manners.

At the operation 354, the media mix data generation engine 242 operatesto divide the beginning portion (P1) into a predetermined number ofsegments, such as S1-S6 (FIG. 8). In some embodiments, the segments aredivided in the same time length. In other embodiments, at least one ofthe segments has different time lengths. In the illustrated example ofFIG. 8, the beginning portion (P1) is divided into six segments S1-S6.However, the number of segments is not limited to six and can be anynumber.

In some embodiments, the segments (e.g., S1-S6) are defined by bars(e.g., B1-B6) within the beginning portion (P1) of the media contentitem 212. A bar is a segment of time corresponding to a specific numberof beats in which each beat is represented by a particular note value,and the boundaries of the bar are indicated by vertical bar lines. Inother embodiments, each segment (e.g., S1-S6) is defined by one bar(e.g., B1-B6) as illustrated in FIG. 8. In other embodiments, eachsegment (e.g., S1-S6) is defined by two or more bars (e.g., B1-B6).

At the operation 356, the media mix data generation engine 242 operatesto determine a musical energy (E) for each segment (S1-S6). In someembodiments, a musical energy (E) for each segment (S1-S6) is determinedas the average of variations in the musical energy over that segment.Other methods for calculating the musical energy (E) for each segmentare also possible.

At the operation 358, the media mix data generation engine 242 operatesto select a segment having the highest musical energy. In theillustrated example of FIG. 8, the segment (S6) has the highest musicalenergy (E6), and therefore is selected as a mix-in segment (S_(IN)) bythe media mix data generation engine 242.

At the operation 360, the media mix data generation engine 242 operatesto define the beginning of the selected segment as a mix-in point(T_(IN)). In the illustrated example of FIG. 8, the beginning of thesegment (S6) is determined to be the mix-in point (T_(IN)) of the mediacontent item 212.

Referring to FIG. 7, some embodiments of the method 370 includesoperations 372, 374, 376, 378, and 380. The method 370 can be performedsimilarly to the method 350.

At the operation 372, the media mix data generation engine 240 operatesto determine a predetermined ending portion of the media content item212 that ends with the end (T=T_(f)) of the media content item 212. Insome embodiments, the predetermined ending portion is a last portion ofa plurality of identically-divided portions of the media content item212. For example, as illustrated in FIG. 8, where the media content item212 is divided by six portions having the same length, the predeterminedending portion of the media content item 212 is the last portion (P6) ofthe media content item 212, which is a portion of the media content item212 in a time range of five sixth (5×T_(f)/6) to the end (T_(f)) of theentire time length. In other embodiments, the predetermined beginningportion can be defined in different manners.

At the operation 374, the media mix data generation engine 242 operatesto divide the ending portion (P6) into a predetermined number ofsegments, such as S7-S12 (FIG. 8). In some embodiments, the segments aredivided in the same time length. In other embodiments, at least one ofthe segments has different time lengths. In the illustrated example ofFIG. 8, the ending portion (P6) is divided into six segments S7-S12.However, the number of segments is not limited to six and can be anynumber.

In some embodiments, the segments (e.g., S7-S12) are defined by bars(e.g., B7-B12) within the ending portion (P6) of the media content item212. In other embodiments, each segment (e.g., S7-S12) is defined by onebar (e.g., B7-B12) as illustrated in FIG. 8. In other embodiments, eachsegment (e.g., S7-S12) is defined by two or more bars (e.g., B7-B12).

In some embodiments, the segments (e.g., S7-S12) in the ending portion(e.g., P6) are defined to not only have the same time lengthstherebetween, but have the same time lengths of the segments (e.g.,S1-S6) of the beginning portion (e.g., P1) of the media content item212. As a plurality of media content items 212 are analyzed in the samemanner as described in FIGS. 6 and 7, a segment including a mix-outpoint in an ending portion of a content media item can completelyoverlap a segment including a mix-in point in a beginning portion of asubsequent content media item, when the two content media items arecrossfaded for smooth transition. This ensures a smooth overlap betweenthe content media items.

In other embodiments, the time length of segments in ending portions ofmedia content items can be different from the time length of segment inbeginning portion of the media content items.

At the operation 376, the media mix data generation engine 242 operatesto determine a musical energy (E) for each segment (S7-S12). In someembodiments, a musical energy (E) for each segment (S7-S12) isdetermined as the average of variations in the musical energy over thatsegment. Other methods for calculating the musical energy (E) for eachsegment are also possible.

At the operation 378, the media mix data generation engine 242 operatesto select a segment having the highest musical energy. In theillustrated example of FIG. 8, the segment (S9) has the highest musicalenergy (E9), and therefore is selected as a mix-out segment (S_(OUT)) bythe media mix data generation engine 242.

At the operation 380, the media mix data generation engine 242 operatesto define the beginning of the selected segment as a mix-out point(T_(OUT)). In the illustrated example of FIG. 8, the beginning of thesegment (S9) is determined to be the mix-out point (T_(OUT)) of themedia content item 212.

FIG. 9 illustrates an example crossfade data 400 including informationabout the mix-in points (T_(IN)) and mix-out points (T_(OUT)) of themedia content items 212. In some embodiments, the data 400 includes amedia content item ID column 402, a mix-in point column 404, and amix-out point column 406.

The media content item ID column 402 contains attributes that are usedto identify each media content item 212.

The mix-in point column 404 contains information about mix-in points(T_(IN)) of media content items 212.

The mix-out point column 406 contains information about mix-out points(Tour) of the media content items 212.

In some embodiments, the crossfade data 400 is incorporated in therepetitive-motion activity media metadata 232. In other embodiments, thecrossfade data 400 is maintained separately from the repetitive-motionactivity media metadata 232.

Referring to FIGS. 10 and 11, an example method of playing back mediacontent items with smooth transitions therebetween to continuouslysupport a user's repetitive motion activity. In particular, FIG. 10 is aflowchart illustrating an example method 420 of performing the operation304 of FIG. 3, and FIG. 11 illustrates the method 420 with two mediacontent items 212A and 212B.

Referring now to FIG. 10, some embodiments of the method 420 includeoperations 422, 424, and 426.

In some embodiments, the media-playback device 102 including thecadence-based media content crossfade engine 112 is configured toexecute the method 420. Although it is described in this document thatthe media-playback device 102 (including the cadence-based media contentcrossfade engine 112) is used to perform the method 420, it is apparentthat the method 420 can be performed by other computing devices in otherembodiments.

At the operation 422, the media-playback device 102 (e.g., thecadence-based media content crossfade engine 112) operates to receivethe crossfade data 400 from the media-delivery system 104. The crossfadedata 400 contain information about mix-in and mix-out points for mediacontent items 212 (including a first media content item 212A and asecond media content item 212B) that are to be played back on themedia-playback device 102.

At the operation 424, the media-playback device 102 operates to playback the first media content item 212A having a tempo corresponding to auser's cadence acquired by the media-playback device 102 while the userperforms a repetitive motion activity (e.g. running) as described above.

At the operation 426, the media-playback device 102 starts playing backthe second media content item 212B as the first media content item 212Aapproaches to its end. Similarly to the first media content item 212A,the second media content item 212B has a tempo corresponding to theuser's cadence. In some embodiments, the media-playback device 102 playsthe second media content item 212B while playing back the first contentmedia item 212A during the user's repetitive motion activity such thatthe mix-in point (T_(IN)) of the second media content item 212B matchesthe mix-out point (T_(OUT)) of the first media content item 212A.

As illustrated in FIG. 11, the mix-out point (T_(OUT)) of the firstcontent media item 212A is aligned with the mix-in point (T_(IN)) of thesecond content media item 212B, and the first and second media contentitems 212A and 212B are crossfaded around the mix-in and mix-out points(T_(IN) and T_(OUT)). As described above, the first and second mediacontent items 212A and 212B are selected by the media-playback device102 to have a tempo corresponding to the user's cadence. Therefore, themedia-playback device 102 can play back the first and second mediacontent items 212A and 212B with smooth transition therebetween, whichmaintaining substantially consistent musical energy throughout the twomedia content items 212A and 212B (e.g., maintaining substantially equalpower before, during, and after transitions). In some embodiments, alimiter is provided to manage the musical energy of media content itemsto substantially an equal level over transitions between the mediacontent items. A limiter is a circuit that allows signals below aspecified input power to pass unaffected while attenuating the peaks ofstronger signals that exceed that input power. In some embodiments, thelimiter can perform a dynamic range compression (DRC).

As the media-playback device 102 operates to play back a plurality ofmedia content items 212 in this manner, a consistent musical energysuitable for a user's repetitive motion activity can continue overtransitions between different media content items 212. Further, as aplurality of media content items 212 are selected to have a tempocorresponding to a user's cadence, the media content items 212 need notbe processed to match the tempo therebetween.

FIG. 12 illustrates an example method of aligning the mix-out point(T_(OUT)) of the first media content item 212A and the mix-in point(T_(IN)) of the second media content item 212B. In some embodiments, asthe mix-in point (T_(IN)) and the mix-out point (T_(OUT)) are matched,the media-playback device 102 can operate to match at least one beat 440(including 440A-440D) in the mix-out segment (S_(OUT)) of the firstmedia content item 212A with at least one beat 442 (including 442A-442D)in the mix-in segment (S_(IN)) of the second media content item 212B.

In some embodiments, when the mix-out point (T_(OUT)) of the first mediacontent item 212A is aligned with the mix-in point (T_(IN)) of thesecond media content item 212B, a downbeat 440A in the mix-out segment(e.g., bar) (S_(OUT)) of an ending portion of the first media contentitem 212A matches a downbeat 442A in the mix-in segment (e.g., bar)(S_(IN)) of a beginning portion of the second media content item 212B.Since the consecutive media content items 212 (e.g., a first mediacontent item 212A and a second media content item 212B) are selected tohave the same tempo or similar tempi, which correspond to a user'scadence, segments in an ending portion of the first media content item212A have the same beats as in segments in a beginning portion of thesecond media content item 212B. Therefore, when the downbeats 440A and440B are matched with the first and second media content items 212A and212B overlapping, all of the beats 440 and 442 in the overlappedsegments (i.e., the segment in the ending portion of the first mediacontent item and the segment in the beginning portion of the secondmedia content item) can be aligned.

In other embodiments, other beats in the mix-out segment (S_(OUT)) andmix-in segment (S_(IN)) can be used for the beat matching as describedabove. In yet other embodiments, multiple beats from the mix-out segment(S_(OUT)) and mix-in segment (S_(IN)) can be used to be matched insimilar manners. In yet other embodiments, one or more beats around themix-out segment (S_(OUT)) and mix-in segment (S_(IN)) (but notnecessarily within the mix-out segment (S_(OUT)) and mix-in segment(S_(IN))) can be used for the beat matching.

In some cases, at least one of the beats 440 of the first media contentitem 212A are not completely aligned with at least one of the beats 442of the second media content item 212B when the first and second contentitems are crossfaded. Although the beats of the first media content itemcan be off-phased with the beats of the second media content item, theuser will not be distracted very much because the same tempo continuesonce the overlapped portion ends and the second media content item isonly played back.

Referring to FIGS. 13 and 14, another example method of playing backmedia content items with smooth transitions therebetween to continuouslysupport a user's repetitive motion activity. In particular, FIG. 13 is aflowchart illustrating an example method 450 of performing the operation304 of FIG. 3, and FIG. 14 illustrates the method 450 with two mediacontent items 212A and 212B. The method 450 is similar to the method 420except that media content items 212 are overlapped during predeterminedduration. Thus, the description for the method 420 with reference toFIGS. 10-12 is incorporated by reference for the method 450.

Referring to FIG. 13, some embodiments of the method 450 includeoperations 452, 454, 456, 458, and 460.

In some embodiments, the media-playback device 102 including thecadence-based media content crossfade engine 112 is configured toexecute the method 450. Although it is described in this document thatthe media-playback device 102 (including the cadence-based media contentcrossfade engine 112) is used to perform the method 450, it is apparentthat the method 450 can be performed by other computing devices in otherembodiments.

At the operation 452, the media-playback device 102 (e.g., thecadence-based media content crossfade engine 112) operates to receivethe crossfade data 400 from the media-delivery system 104. The crossfadedata 400 contain information about mix-in and mix-out points for mediacontent items 212 (including a first media content item 212A and asecond media content item 212B) that are to be played back on themedia-playback device 102.

At the operation 454, the media-playback device 102 operates to obtaincrossfade duration (T_(D)) (FIG. 14). In some embodiments, the crossfadeduration can be selected by a user. For example, the media-playbackdevice 102 provides a user interface 470 (FIG. 15) to prompt a user toselect the crossfade duration. An example user interface 470 isdescribed and illustrated in more detail with reference to FIG. 15. Inother embodiments, the crossfade duration can be automatically adjustedby the media-playback device 102 based on various factors, such as alevel of musical energy as defined herein.

At the operation 456, the media-playback device 102 operates to playback the first media content item 212A having a tempo corresponding to auser's cadence acquired by the media-playback device 102 while the userperforms a repetitive motion activity (e.g. running) as described above.

At the operation 458, the media-playback device 102 starts playing backthe second media content item 212B as the first media content item 212Aapproaches to its end. Similarly to the first media content item 212A,the second media content item 212B has a tempo corresponding to theuser's cadence. In some embodiments, the media-playback device 102 playsthe second media content item 212B while playing back the first contentmedia item 212A during the user's repetitive motion activity such thatthe mix-in point (T_(IN)) of the second media content item 212B matchesthe mix-out point (T_(OUT)) of the first media content item 212A.

In this example, the media-playback device 102 starts playing back thesecond media content item 212B at a time (T_(START)) ahead of the mix-inpoint (T_(IN)) of the second media content item 212B. In someembodiments, the time (T_(START)) is defined as a time a half (T_(D)/2)of the crossfade duration (T_(D)) ahead of the mix-in point (T_(IN)) ofthe second media content item 212B. In other embodiments, the time(T_(START)) can be defined differently, such as a time a quarter(T_(D)/4) of the crossfade duration (T_(D)) ahead of the mix-in point(T_(IN)) of the second media content item 212B.

At the operation 460, the media-playback device 102 operates to stopplaying back the first media content item 212A while playing back thesecond media content item 212B. In some embodiments, the media-playbackdevice 102 ceases to play back the first media content item 212A at atime (T_(END)) after the mix-out point (T_(OUT)) of the first mediacontent item 212A. In some embodiments, the time (T_(END)) is defined asa time a half (T_(D)/2) of the crossfade duration (T_(D)) after themix-out point (T_(OUT)) of the first media content item 212A. In otherembodiments, the time (T_(END)) can be defined differently, such as atime a quarter (T_(D)/4) of the crossfade duration (T_(D)) after themix-out point (T_(OUT)) of the first media content item 212A.

As the method 450 is performed similarly to the method 420, all of thefeatures and advantages of the method 420 are also achieved in themethod 450. In addition, the crossfade duration employed in the method450 can selectively reduce an overlap time between media content itemsand therefore allow much smooth transitions between media content items.

In some embodiments, the crossfade duration (T_(D)) is determined by anumber of beats around the mix-in and mix-out points that are aligned.By way of example, the crossfade duration (T_(D)) is set to include twobeats prior to the aligned mix-in and mix-out points and two beats afterthe aligned mix-in and mix-out points. In other examples, the crossfadeduration (T_(D)) can be determined to include a different number (i.e.,other than two) of beats before and after mix-in and mix-out points. Insome embodiments, the number of beats before the aligned mix-in andmix-out points can be the same as the number of beats after the alignedmix-in and mix-out points. In other embodiments, the number of beatsbefore the aligned mix-in and mix-out points can be different from thenumber of beats after the aligned mix-in and mix-out points.

FIG. 15 is an example user interface 470 for selecting the crossfadeduration (T_(D)). In some embodiments, the user interface 470 isprovided on the media-playback device 102. The user interface 470includes a crossfade selection control 472 configured to select a lengthof the crossfade duration (T_(D)). In some embodiments, the crossfadeselection control 472 provides preset upper and lower limits 474A and474B so that a user adjusts the crossfade duration (T_(D)) therebetween.In the illustrated example, the crossfade selection control 472 isdescribed as a horizontal adjust bar. In other embodiments, thecrossfade selection control 472 can be of various other types.

As noted previously, although many of the examples provided above aredescribed with respect to running, other embodiments relate to otherrepetitive motion activities as well such as cycling, swimming, androwing.

As used herein, “about” refers to a degree of deviation based onexperimental error typical for the particular property identified. Thelatitude provided the term “about” will depend on the specific contextand particular property and can be readily discerned by those skilled inthe art. The term “about” is not intended to either expand or limit thedegree of equivalents which may otherwise be afforded a particularvalue. Further, unless otherwise stated, the term “about” shallexpressly include “exactly,” consistent with the discussions regardingranges and numerical data. It is to be understood that a numerical rangeis used merely for convenience and brevity and thus should beinterpreted flexibly to include not only the numerical values explicitlyrecited as the limits of the range, but also to include all theindividual numerical values or sub-ranges encompassed within that rangeas if each numerical value and sub-range is explicitly recited. As anillustration, a numerical range of “about 4 percent to about 7 percent”should be interpreted to include not only the explicitly recited valuesof about 4 percent to about 7 percent, but also include individualvalues and sub-ranges within the indicated range. Thus, included in thisnumerical range are individual values such as 4.5, 5.25 and 6 andsub-ranges such as from 4-5, from 5-7, and from 5.5-6.5; etc. This sameprinciple applies to ranges reciting only one numerical value.Furthermore, such an interpretation should apply regardless of thebreadth of the range or the characteristics being described.

The various examples and teachings described above are provided by wayof illustration only and should not be construed to limit the scope ofthe present disclosure. Those skilled in the art will readily recognizevarious modifications and changes that may be made without following theexample examples and applications illustrated and described herein, andwithout departing from the true spirit and scope of the presentdisclosure.

What is claimed is:
 1. A method of continuously playing back a pluralityof media content items, the method comprising: dividing a first mediacontent item into a plurality of sections, including an ending section;dividing the ending section into a plurality of segments; determining avalue of a musical attribute for each of the plurality of segments ofthe ending section; identifying a mix-out point of the first mediacontent item within a segment of the ending section having the musicalattribute with a target value; playing back the first media content itemon a media playback device; determining an alignment of the mix-outpoint of the first media content item with a mix-in point of a secondmedia content item; and playing back the second media content item onthe media playback device based on the determined alignment.
 2. Themethod of claim 1, further comprising: defining a beginning of thesegment of the ending section having the musical attribute with thetarget value as the mix-out point of the first media content item. 3.The method of claim 1, wherein determining the value of the musicalattribute for each of the plurality of segments of the ending sectioncomprises: determining the value based on variations in the musicalattribute over the respective segment of the ending section.
 4. Themethod of claim 1, further comprising: determining a mix-in point forthe first media content item; and playing back the first media contentitem on the media playback device based on the mix-in point.
 5. Themethod of claim 4, wherein the plurality of sections into which thefirst media content item is divided further includes a beginningsection, and determining the mix-in point for the first media contentitem comprises: dividing the beginning section into a plurality ofsegments; determining a value of a musical attribute for each of theplurality of segments in the beginning section; and identifying themix-in point of the first media content item within a segment of thebeginning section having the musical attribute with a target value. 6.The method of claim 4, further comprising: generating crossfade dataincluding the mix-in point and the mix-out point of the first mediacontent item, wherein the crossfade data is stored in association withthe first media content item.
 7. The method of claim 1, furthercomprising: playing back the second media content item on the mediaplayback device further based on a crossfade duration.
 8. A method ofcontinuously playing back a plurality of media content items, the methodcomprising: playing back a first media content item on a media playbackdevice; dividing a second media content item into a plurality ofsections, including a beginning section; dividing the beginning sectioninto a plurality of segments; determining a value of a musical attributefor each of the plurality of segments of the beginning section;identifying a mix-in point of the second media content item within asegment of the beginning section having the musical attribute with atarget value; determining an alignment of a mix-out point of the firstmedia content item with the mix-in point of the second media contentitem; and playing back the second media content item on the mediaplayback device based on the determined alignment.
 9. The method ofclaim 8, further comprising: defining a beginning of the segment of thebeginning section having the musical attribute with the target value asthe mix-in point of the second media content item.
 10. The method ofclaim 8, wherein determining the value of the musical attribute for eachof the plurality of segments of the beginning section comprises:determining the value based on variations in the musical attribute overthe respective segment of the beginning section.
 11. The method of claim8, further comprising: determining a mix-out point for the second mediacontent item; determining an alignment of the mix-out point of thesecond media content item with a mix-in point of a third media contentitem; and playing back the third media content item on the mediaplayback device based on the determined alignment.
 12. The method ofclaim 11, wherein the plurality of sections into which the second mediacontent item is divided further includes an ending section, anddetermining the mix-out point for the second media content itemcomprises: dividing the ending section into a plurality of segments;determining a value of a musical attribute for each of the plurality ofsegments in the ending section; and identifying the mix-out point of thesecond media content item within a segment of the ending section havingthe musical attribute with a target value.
 13. The method of claim 11,further comprising: generating crossfade data including the mix-in pointand the mix-out point of the second media content item, wherein thecrossfade data is stored in association with the second media contentitem.
 14. A method of providing a continuous transition during playbackof a plurality of media content items, the method comprising: dividing afirst media content item and a second media content item into aplurality of sections, including a beginning section and an endingsection; dividing the ending section of the first media content iteminto a plurality of ending section segments and the beginning section ofthe second media content item into a plurality of beginning sectionsegments; determining a value of a musical attribute for each of theplurality of ending section segments of the first media content item andthe plurality of beginning section segments of the second media contentitem; identifying a mix-out point of the first media content item withina ending section segment having the musical attribute with a firsttarget value and a mix-in point of the second media content item withina beginning section segment having the musical attribute with a secondtarget value; storing the mix-out point of the first media content itemas mix-out point data for the first media content item and the mix-inpoint of the second media content item as mix-in point data for thesecond media content item; and transmitting the mix-out point data andthe mix-in point data to a media playback device for playback of thefirst media content item and the second media content item on the mediaplayback device with the mix-out point of the first media content itemaligned with the mix-in point of the second media content item.
 15. Themethod of claim 14, wherein the value of the musical attributerepresents a power associated with the musical attribute.
 16. The methodof claim 14, wherein the musical attribute includes one or more oftempo, pitch, dynamics, articulation, timbre, or order.
 17. The methodof claim 14, wherein the alignment of the mix-out point of the firstmedia content item with the mix-in point of the second media contentitem is adjusted to match at least one beat within the segment of theending section of the first media content item with at least one beatwithin the segment of the beginning section of the second media contentitem.
 18. The method of claim 14, wherein the first target value is ahighest value of the musical attribute across the plurality of endingsection segments of the first media content item, and the second targetvalue is a highest value of the musical attribute across the pluralityof beginning section segments of the second media content item.
 19. Themethod of claim 14, further comprising: adjusting at least one of thefirst target value and the second target value to equalize the firsttarget value and the second target value when transitioning between thefirst media content item and the second media content item.
 20. Themethod of claim 14, further comprising: acquiring a cadence of arepetitive motion activity of a user; determining a tempo based on theacquired cadence; and selecting the first media content item and thesecond media content item based on the tempo.